East Koy Creek Angler Use and Electrofishing Studies (2011-2013)

Background

As part of a three year, state-wide evaluation of New York's inland stream trout stocking program, the fishery of East Koy Creek was studied intensively from 2011 through 2013. This study involved surveys of angler use, catch and harvest rates. We also used electrofishing to evaluate the number of wild and stocked brown trout in the stream, immediately after stocking and in the late summer of each year. DEC Region 9 Fisheries Staff carried out fish population sampling, while a seasonal technician counted and interviewed anglers. Data compilation and analysis was performed by researchers from Cornell University, under DEC contract . Findings from the 2011-2013 studies were compared with similar surveys done by DEC in 1996 and 1997 on East Koy Creek.

Angler Use Surveys

Nineteen inch wild brown trout from
East Koy Creek.

For all three years, a total of 223 days were surveyed, resulting in 1,457 angler interviews. The vast majority of these interviews were in April, with low angler effort seen through the summer and into the fall. The total estimated angling effort for all three years was 25,926 hours, with April angling accounting for 61%-76% of the total. Opening day (April 1st) effort accounted for an average of 20% of the total over the three years. Opening day effort is very dependent on weather and stream flows, and we noted much variation with 2,309 hours of effort April 1st in 2011, 1,697 hours in 2012 and 1,065 hours in 2013. In order to compare effort from one stream to another, we express angler effort in hours per acre of stream stocked. Angler effort from 2011 to 2013 dropped from 213 to 152 hours per acre (Table 1). You will note that there has been considerable variation in angler effort, but effort during the current study years was one half to one fifth of that found in 1996 and 1997. Angler effort in the 2011-2013 studies is considered light to moderate fishing intensity for New York State.

Anglers reported catching 2,341 trout over the three year study; angler catch rates varied from 0.71 trout per hour in 2011 to 0.89 trout per hour in 2013 (Table 1). Catch rate values were lower than those found in 1996 and 1997 surveys, but were still above the statewide goal for stocked streams. The goal for a stocked stream in NY is to have an average catch rate of 0.5 fish per hour (one trout caught for 2 hours of fishing). Anglers reported releasing a high percentage of the trout they caught in all three years (73%-78%), which is similar to 1996 and 1997 (Table 1). These high release rates are considerably different than what was common when our trout stocking policies were developed in the 1980s. At that time, most legal size trout caught were kept by anglers.

Fish Population Sampling

Electrofishing East Koy Creek.

In early-May and again in late-August in all three years, Region 9 Fisheries staff, assisted by angler volunteers conducted trout population sampling on East Koy Creek. The same four sites were electrofished each time. Analysis showed that the number of stocked trout remaining in the stream had declined steeply by May and that very few remained in August. Remaining hatchery trout included fish from all three stocking increments (March, April and May). Moderate numbers of wild brown trout were also sampled (mainly at the upstream-most site with the best water temperatures) all three years and were similar to the numbers of wild brown trout found in 1996 and 1997 (Table 1).

Conclusion

Overall, densities of hatchery trout remaining in the stream during electrofishing surveys were far lower than expected based on high release rates of trout reported by anglers. This indicates stocked trout survival is much poorer than it was 30 years ago when our state-wide trout stocking policies were developed. This may be due to trout mortality and/or migration of trout out of the stocking section. Wild trout density appears to have remained very stable in East Koy Creek since 1996.

Although plenty of trout remained in the stream to provide good fishing, the angler survey showed very little angler effort occurred from late-August to mid-October. Anglers are missing out on a good time of year to fish in East Koy Creek. In-depth data analysis of the angler effort and electrofishing surveys across New York is being completed by Cornell University, as part of the state-wide "fate of stocked trout" study and results for all survey streams should be available later in 2014. Changes to statewide trout stocking policies in future years will be based on the findings of these studies.

Table 1. Results from angler use and fish sampling studies on East Koy Creek in 1996, 1997, 2011, 2012 and 2013.